Eruptive activity at Pavlof Volcano continues at a low level. Relatively continuous, low-level tremor has characterized the seismicity over the past 24 hours and persistent thermal signals have been observed in satellite data. The thermal features and level of seismic activity are consistent with minor emissions of ash, gas and steam and possible low-level lava fountaining. Overall, the volcano is relatively quiet.

It is possible for conditions to change at any time and more vigorous seismicity and ash emissions may result. Pavlof Volcano often experiences fluctuating levels of eruptive activity and lengthy periods of low-level activity lasting for weeks or more may be punctuated by periods of vigorous lava fountaining and ash emission. Typically, the build up to such activity is gradual and would be identified during routine analysis of seismic, satellite and other monitoring data.

Nearly continuous volcanic tremor and small explosions have been detected in seismic data throughout the past 24 hours and satellite observations continue to show elevated surface temperatures at the intracaldera cone of Veniaminof Volcano. These data indicate an ongoing low-level eruption characterized by effusion of lava and emission of minor amounts of ash and steam. Web camera images of the volcano from Perryville throughout the past 24 hours have been obscured by clouds and fog.

It remains possible for activity at Veniaminof Volcano to increase above its current level at any time and more vigorous ash emissions may occur. Sustained periods of volcanic tremor may correspond with episodes of continuous ash emission which may not be detected in satellite data, especially if ash plumes remain below 15,000 to 20,000 feet above sea level. Brief bursts of ash emission and small explosions may result in ash fall on the flanks of the volcano, and this is likely to occur while the volcano is at its current level of unrest. A vigorous explosive episode that produces a large ash cloud is not expected at the level of unrest that has been occurring over the past several weeks; however, this remains a possible, but not certain outcome of the present eruption. The lava flow may continue to grow slowly and is not expected to lead to any significant hydrologic events in the drainages north of the volcano associated with melting of snow and ice.

No elevated surface temperatures or other outward signs of unrest were observed in satellite images over the past week. AVO has received no other reports of activity at the volcano.

Sudden explosions of blocks and ash are possible with little or no warning and ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff. However, for some events, detection may not be possible for several hours. Cleveland volcano does not have a local seismic network and is monitored using only distant seismic and infrasound instruments and satellite data.

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

VOLCANO ALERT LEVELS

NORMALVolcano is in typical background, noneruptive state or, after a change from a higher level, volcanic activity has ceased and volcano has returned to noneruptive background state.

ADVISORYVolcano is exhibiting signs of elevated unrest above known background level or, after a change from a higher level, volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.

WATCHVolcano is exhibiting heightened or escalating unrest with increased potential of eruption, timeframe uncertain, OR eruption is underway but poses limited hazards.

WARNINGHazardous eruption is imminent, underway, or suspected.

AVIATION COLOR CODES

GREENVolcano is in typical background, noneruptive state or, after a change from a higher level, volcanic activity has ceased and volcano has returned to noneruptive background state.

YELLOWVolcano is exhibiting signs of elevated unrest above known background level or, after a change from a higher level, volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.

ORANGEVolcano is exhibiting heightened or escalating unrest with increased potential of eruption, timeframe uncertain, OR eruption is underway with no or minor volcanic-ash emissions [ash-plume height specified, if possible].

REDEruption is imminent with significant emission of volcanic ash into the atmosphere likely OR eruption is underway or suspected with significant emission of volcanic ash into the atmosphere [ash-plume height specified, if possible].